绵羊Leptin基因的进化分析

Evolution Analysis of Leptin Gene in Sheep

[目的]为绵羊与其他动物的分子系统进化分析奠定基础。[方法]对绵羊Leptin基因的第23、外显子进行PCR扩增和测序,将测序结果与GenBank中绵羊和7个其他物种中相应序列进行比对,并构建绵羊与其他物种的分子系统进化树。[结果]不同物种的Leptin基因的核苷酸序列有较高的保守性。绵羊与山羊、水牛、奶牛、猪、人、家鼠、鸡的同源性分别为99.5%、98.0%、97.3%、93.4%、88.4%、83.9%、82.4%。系统发生树将这些物种总体上分成2支,家鼠与鸡聚为一支;而绵羊与山羊、水牛、猪和人为另一支。绵羊与山羊亲缘关系最近,而与水牛、奶牛、猪、人、家鼠、鸡亲缘关系渐远。[结论]Leptin基因适于进行物种起源、演化、分类以及系统发生关系的研究。

[Objective] The research aimed to lay the foundation for molecular phylogenetic evolution analysis of sheep and other animals.[Method] The 2nd and 3rd exon of Leptin gene in sheep was amplified and sequenced.The sequencing results were compared with the corresponding sequences in sheep and other 7 species in GenBank and the molecular phylogenetic evolution tree of sheep and other species was constructed.[Result] The nucleotide sequences of Leptin gene in different species were highly conservative.The homologies between sheep and goat,water buffalo,milch cow,pig,human,house mouse and chicken were 99.5%,98.0%,97.3%,93.4%,88.4%,83.9%,82.4% resp.The phylogenetic tree classified these species into 2 branches as a whole,in which the house mouse and chicken were on one branch and the goat,water buffalo,milch cow,pig and human were on other branch.The genetic relationship between sheep and goat was closest,while the genetic relationship between sheep and water buffalo,milch cow,pig,human house mouse and chicken be came farther gradually.[Conclusion] Leptin gene was suitable for studying the species origin,evolvement,classification and phylogenetic relationship.